<template>
    <div class="app-picture-preview">
        <ul class="">
            <li v-for="(file, index) in files" :key="index" class="preview-file-list-item">
                <div class="preview-file-list-img">
                    <el-image :src="file.url" class="" style="">
                        <div slot="error" class="image-slot">
                            <img src="/assets/img/picture.png" style="width: 100%; height: 100%" />
                        </div>
                    </el-image>
                    <div class="preview-file-list-actions">
                        <span class="action-preview">
                            <i class="el-icon-zoom-in" @click="onPreview(file)"></i>
                        </span>
                        <span class="action-download">
                            <i class="el-icon-download" @click="onDownload(file)"></i>
                        </span>
                    </div>
                </div>
            </li>
        </ul>
        <!-- 预览 -->
        <modal v-model="dialogVisible" footer-hide width="auto" class-name="app-image-preview-model">
            <el-image :src="dialogImageUrl">
                <div slot="error" class="image-slot">
                    <img src="/assets/img/picture.png" />
                </div>
            </el-image>
        </modal>
    </div>
</template>
<script lang="ts">
import { Vue, Component, Prop, Watch, Provide } from 'vue-property-decorator';
import { Environment } from '@/environments/environment';
import { Subject, Unsubscribable } from 'rxjs';

@Component({})
export default class AppImagePreview extends Vue {
    /**
     * 表单状态
     *
     * @type {Subject<any>}
     * @memberof AppImagePreview
     */
    @Prop() public formState?: Subject<any>;

    /**
     * 表单状态事件
     *
     * @private
     * @type {(Unsubscribable | undefined)}
     * @memberof AppImagePreview
     */
    private formStateEvent: Unsubscribable | undefined;

    /**
     * 初始化值
     *
     * @type {*}
     * @memberof AppImagePreview
     */
    @Prop() public value?: any;

    /**
     * 数据值变化
     *
     * @param {*} newval
     * @param {*} val
     * @returns
     * @memberof AppImagePreview
     */
    @Watch('value')
    onValueChange(newval: any, val: any) {
        this.setFiles(newval);
    }

    /**
     * 所属表单项名称
     *
     * @type {string}
     * @memberof AppImagePreview
     */
    @Prop() public name!: string;

    /**
     * 上传文件路径
     *
     * @memberof AppImagePreview
     */
    public uploadUrl = Environment.BaseUrl + Environment.UploadFile;

    /**
     * 下载文件路径
     *
     * @memberof AppImagePreview
     */
    public downloadUrl = Environment.BaseUrl + Environment.ExportFile;

    /**
     * 文件列表
     *
     * @memberof AppImagePreview
     */
    @Provide() public files = [];

    /**
     * 设置files
     *
     * @private
     * @memberof AppImagePreview
     */
    private setFiles(value: any): void {
        let _files = JSON.parse(value);
        if (value && Object.prototype.toString.call(_files) == '[object Array]') {
            this.files = _files;
            this.files.forEach((file: any) => {
                let url = `${this.downloadUrl}/${file.id}`;
                file.url = url;
            });
        } else {
            this.files = [];
        }
    }

    /**
     * vue 生命周期
     *
     * @memberof AppImagePreview
     */
    public created() {
        if (this.formState) {
            this.formStateEvent = this.formState.subscribe(($event: any) => {
                // 表单加载完成
                if (Object.is($event.type, 'load')) {
                    this.setFiles(this.value);
                }
            });
        }
    }

    /**
     * vue 生命周期
     *
     * @memberof AppImagePreview
     */
    public mounted() {
        this.setFiles(this.value);
    }

    /**
     * 组件销毁
     *
     * @memberof AppImagePreview
     */
    public destroyed(): void {
        if (this.formStateEvent) {
            this.formStateEvent.unsubscribe();
        }
    }

    /**
     * 下载文件
     *
     * @param {*} file
     * @memberof AppImagePreview
     */
    public onDownload(file: any) {
        window.open(file.url);
    }

    /**
     * 预览图片地址
     *
     * @type {string}
     * @memberof AppImagePreview
     */
    public dialogImageUrl: string = '';

    /**
     * 是否显示预览界面
     *
     * @type {boolean}
     * @memberof AppImagePreview
     */
    public dialogVisible: boolean = false;

    /**
     * 预览
     *
     * @param {*} file
     * @memberof AppImagePreview
     */
    public onPreview(file: any) {
        this.dialogImageUrl = file.url;
        this.dialogVisible = true;
    }
}
</script>
<style lang="less">
@import './app-image-preview.less';
</style>
